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diff --git a/packages/noncvs/windows/extra/Gem/dev/Gem/ContextData.h b/packages/noncvs/windows/extra/Gem/dev/Gem/ContextData.h
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+++ b/packages/noncvs/windows/extra/Gem/dev/Gem/ContextData.h
@@ -0,0 +1,149 @@
+/*-----------------------------------------------------------------
+  LOG
+  GEM - Graphics Environment for Multimedia
+
+  data specific to a rendering context
+
+  Copyright (c) 2009-2011 IOhannes m zmölnig. forum::für::umläute. IEM. zmoelnig@iem.at
+  For information on usage and redistribution, and for a DISCLAIMER OF ALL
+  WARRANTIES, see the file, "GEM.LICENSE.TERMS" in this distribution.
+
+  -----------------------------------------------------------------*/
+
+#ifndef _INCLUDE__GEM_GEM_CONTEXTDATA_H_
+#define _INCLUDE__GEM_GEM_CONTEXTDATA_H_
+
+#include "Gem/ExportDef.h"
+#include <vector>
+
+/*-----------------------------------------------------------------
+  -------------------------------------------------------------------
+  CLASS
+  ContextData
+    
+  rendering context specific data
+  this is heavily inspired by VrJuggler
+
+  DESCRIPTION
+
+  several things in openGL like display-lists are context dependent
+  if we have multiple contexts, such values most be generated for each context
+  ContextData provides a generic (templated) datatype for this
+
+  LATER (SOONER) think about splitting the render() into a context-specific section that 
+  set's up display-lists,... and a draw() function that just calls the pre-generated values
+    
+  -----------------------------------------------------------------*/
+
+namespace gem {
+
+class GEM_EXTERN ContextDataBase {
+ protected:
+  static const int INVALID_CONTEXT;
+  virtual int getCurContext(void);
+  virtual ~ContextDataBase(void);
+};
+
+
+template<class ContextDataType = int>
+  class GEM_EXTERN ContextData : ContextDataBase
+  {
+    private:
+    public:
+   
+    //////////
+    // Constructor
+    ContextData(void) : m_haveDefaultValue(false) {;}
+
+    ContextData(ContextDataType v) : m_haveDefaultValue(true), m_defaultValue(v) {;}
+
+    virtual ~ContextData() {
+      m_ContextDataVector.clear();
+    }
+    	
+    /**
+     * returns the context-specific value
+     *
+     * @usage ContextData<GLenum>m_fun; m_fun=GL_FUNC_ADD;
+     *
+     * @pre We are in a draw process.
+     * @note Should only be called from the draw function.
+     *        Results are un-defined for other functions.
+     */
+    virtual operator ContextDataType()
+    {
+      return (*getPtrToCur());
+    }
+
+    /**
+     * assigns a value to the correct context
+     *
+     * @pre We are in a draw process.
+     * @note Should only be called from the draw function.
+     *       Results are un-defined for other functions.
+     */
+    virtual ContextDataType&operator = (ContextDataType value)
+    {
+      /* simplistic approach to handle out-of-context assignments:
+       *  assign the value to all context instances
+       */
+      if(INVALID_CONTEXT==getCurContext()) {
+        doSetAll(value);
+      }
+
+      return (*getPtrToCur()=value);
+    }
+
+    private:
+    bool m_haveDefaultValue;
+    ContextDataType m_defaultValue;
+    std::vector<ContextDataType*>  m_ContextDataVector;
+
+
+    /* Makes sure that the vector is at least requiredSize large */
+    void checkSize(unsigned int requiredSize)
+    {
+      if(requiredSize > m_ContextDataVector.size())
+        {
+          m_ContextDataVector.reserve(requiredSize);          // Resize smartly
+          while(m_ContextDataVector.size() < requiredSize)    // Add any new items needed
+            {
+                if(m_haveDefaultValue) {
+                    m_ContextDataVector.push_back(new ContextDataType(m_defaultValue));
+                } else {
+                    m_ContextDataVector.push_back(new ContextDataType);
+                }
+            }
+        }
+    }
+
+    /**
+     * Returns a pointer to the correct data element in the current context.
+     *
+     * @pre We are in the draw function.
+     * @post Synchronized.
+     * @note ASSERT: Same context is rendered by same thread each time.
+     */
+    ContextDataType* getPtrToCur(void)
+    {
+      // Get current context
+      int context_id = getCurContext();
+      // Cache ref for better performance
+      checkSize(context_id+1);     // Make sure we are large enough (+1 since we have index)
+
+      return m_ContextDataVector[context_id];
+    }
+
+    void doSetAll(ContextDataType v)
+    {
+      unsigned int i=0;
+      for(i=0; i< m_ContextDataVector.size(); i++) {
+        *m_ContextDataVector[i]=v;
+      }
+    }
+  };
+};
+
+
+
+#endif	// for header file